Full time! That's it, Arsenal win the 2017 Emirates FA Cup! And it was fully deserved too, Arsene Wenger's men were the better team today against the Premier League champions.
90+3 Sanchez gets a standing ovation as he's replaced by Mohamed Elneny for the final few seconds.
90 Four minutes left for Arsenal to hold on!
87 POST! Ozil breaks away on the right before cutting inside and striking a low shot against the post. It's end to end stuff here. Meanwhile, Michy Batshuayi comes on for Costa.
86 SAVE! Ospina keeps Arsenal's lead in tact with a great reflex save to deny Costa. Tense.
84 It doesn't take Coquelin long to get involved as he's booked within a minute of his arrival.
83 Francis Coquelin joins the fray in place of Oxlade-Chamberlain.
80 Zhaka is added to the referee's notebook for a foul on Willian. The resulting free-kick is headed wide of the post by David Luiz.
78 GOAL!!!!! Unbelievable, Giroud's first contribution is to dig out a wonderful cross into the box which is met perfectly by the head of Ramsey to restore Arsenal's lead.
77 Arsenal make their first substitution as Olivier Giroud comes on for Welbeck.
76 GOAL!!!! Chelsea are back level, as Costa does well to control a cross in the box before smashing a low shot into the bottom corner to level things up. Game on!
72 Chelsea make another change as Willian is introduced at the expense of Pedro.
71 Today's attendance is 89,472 and what a Cup Final they've seen so far.
68 RED CARD! Moses is off, as he picks up a second booking following a lame attempt to win a penalty by diving under Alex Oxlade-Chamberlain's challenge in the area. Spot on from Anthony Taylor and no complaints from Moses as he trudges down the tunnel.
65 SAVE! A great stop from Courtois to keep out Bellerin's shot, after Welbeck had square a pass across the area. Could be crucial, as another Arsenal chance goes begging.
61 Our first substitution of the day sees Cesc Fabregas on for Matic as Chelsea look to add a bit more bite in attack. The switch is greeted by boos from the Arsenal end, for one of their former players.
59 More bookings than Emirates Airlines at the moment, as N'Golo Kante is cautioned for a foul on Aaron Ramsey.
57 Back level on the caution front, as Victor Moses goes in the book for hauling down Danny Welbeck as the Arsenal man brushed past him on the half way line.
54 A yellow card as Rob Holding is cautioned for holding back Costa as the Chelsea striker looked to enter the box from the left.
51 SAVE! Another good stop from the Colombian, this time to keep out Victor Moses' low effort from the right-hand channel of the area.
49 SAVE! Ospina is well placed to keep Kante's deflected shot from 25 yards out as Chelsea start the second half on the front foot.
Kick-off. The teams are back out for the second half and we're underway, with no substitutions for either side.
Half time. The whistle sounds after an entertaining first half, particularly for those of a red persuasion. Arsene Wenger's men have been the better side here, and will probably be asking questions why they aren't more than a goal ahead. On the other side, this is a big half-time team talk for Chelsea boss Antonio Conte who will know his side need to improve after the break.
45+1 A free-kick for Chelsea on the edge of the area is skied over the bar by Marcos Alonso. Poor attempt.
26 Arsenal come close again, as Welbeck's effort is scrambled clear by Chelsea captain Gary Cahill. The Premier League champions are living dangerously here, the Gunners could be three goals up.
24 CHANCE! A delightful pass over the top from Kante sees Diego Costa chase it down and cause confusion between Mertesacker and Ospina. The Blues striker bustles his way through to get a shot in, but Ospina makes a brave block and takes a knock too.
19 POST! Arsenal come so close to doubling their lead as Danny Welbeck heads against the foot of the post from Sanchez's corner on the right. Ramsey tries to turn home the rebound but can only guide it wide. The Gunners are good value for their lead here at the moment.
10 Arsenal's Aaron Ramsey is the first player to go in the boos
4 GOAL!!! Arsenal take the lead through Alexis Sanchez, who chases down a clearance into the box and finishes past Courtois with the outside of his right box. There was an offside flag raised against Ramsey at first, but referee Anthony Taylor appears to have over-ruled his assistant and given the goal.
5.33pm: We're underway, after a minute's silence for this week's tragedy in Manchester. It's Chelsea who get us kicked-off.
5.24pm: The teams are out, ahead of the presentations and the National Anthem.
4:30pm: We have the line-ups for you...
Arsenal: 13 David Ospina, 4 Per Mertesacker (c), 7 Alexis Sanchez, 8 Aaron Ramsey, 11 Mesut Ozil, 15 Alex Oxlade-Chamberlain, 16 Rob Holding, 18 Nacho Monreal, 23 Danny Welbeck, 24 Hector Bellerin, 29 Granit Zhaka.
Substitutes: 33 Petr Cech, 9 Lucas Perez, 12 Olivier Giroud, 14 Theo Walcott, 17 Alex Iwobi, 34 Francis Coquelin, 35 Mohamed Elneny.
Chelsea: 13 Thibaut Courtois, 3 Marcos Alonso, 7 N'Golo Kante, 10 Eden Hazard, 11 Pedro, 15 Victor Moses, 19 Diego Costa, 21 Nemanja Matic, 24 Gary Cahill (c), 28 Cesar Azpilicueta, 30 David Luiz.
Substitutes: 1 Asmir Begovic, 4 Cesc Fabregas, 5 Kurt Zouma, 6 Nathan Ake, 22 Willian, 23 Michy Batshuayi, 26 John Terry.
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